Deep breath. Autumn in India is smog season, the worst time of year for some of the world’s most polluted cities.

There’s a reason for this. In addition to everyday problems such as traffic, industry, domestic cooking and road dust, this is the time of year when farmers set fire to their post-harvest fields. It’s called “stubble burning” – a cheap and easy way to deal with crop residue that needs clearing for the next planting season.

Though technically illegal, it is rife across northern states like Haryana, Punjab and Uttar Pradesh – home to some of India’s most polluted cities: Delhi, Kanpur, Ludhiana and Allahabad. Some estimates say that stubble burning contributes as much as one quarter of the air pollution in Delhi over the winter months.

A study conducted by Harvard’s John A Paulson School of Engineering and Applied Sciences said: “On certain days, during peak fire season, air pollution in Delhi, which is located downwind of the fire, is about 20 times higher than the threshold for safe air as defined by WHO.”

But now a slew of private companies are coming up with a range of offerings they say can help.

A Hamburg-based company called Bio-lutions has set up a factory near Bangalore to convert agricultural residue into fibres that can be used for packing material and tableware. The end products could also help tackle the burgeoning plastic crisis, as they are as cheap as plastic to produce, and take about three months to biodegrade.

As proof of concept, the company ran a pilot for about a year and a half where about 750–1,000kg of agricultural waste was procured each month from a farmer located in Mandya, Karnataka and used to manufacture about 4,000 boxes, which were sold to Big Basket, India’s largest online food and grocery store.

“More than 95% of these farmers were burning such agricultural waste earlier,” said Maheshchandra Guru, director of Vikasana, a sustainable agriculture NGO that works with Bio-lutions.

“Vikasana pays about 500 rupees per tonne of residue collected and per acre of agricultural land generates about 4-5 tonnes of waste, so they earn about 1,500-2,000 rupees additional income each month,” he adds.

Other innovators are also working in the agricultural residue space. Papyrus Australia, an Australian company, has developed a technology that can convert the banana tree trunk into products like paper, packing material and furniture. The technology is especially welcome, considering the huge volume of farm waste on banana plantations in the world’s biggest banana producer.

New Leaf is another innovator company based in New Delhi that is helping farmers use farm waste like rice husk and coconut shells alongside biomass like dung cakes to extract renewable energy in order to power cold-storage and ripening facilities.

“The storage facilities are completely off grid and do not require diesel generating sets,” says Akash Agarwal, director and co-founder of New Leaf. “The machine uses about 40-90kg of waste a day to heat water, and using such hot water, it refrigerates 5,000-30,000kg of fruits and vegetables.”

Named GreenChill, the bio-waste based cold-storage system and ripening chamber is installed on farm. “The facility is completely automatic in the sense that the farmer only needs to dump the waste into the system and it takes care of the rest,” Akash says.

Sumanta Bagchi, a professor at the Indian Institute of Science, says that the rapid commercialisation of farm produce has resulted in a decline in the “pastoral use of farm residue”. “With initiatives like these, farm waste is being put to good use, especially considering how stubble burning contributes to air pollution,” he said.

Speaking about Delhi in particular, Bagchi notes that during winters, windless weather conditions help trap airborne pollutants to initiate a smog over the city. “The pollution from crop burning from in and around Delhi only adds to this problem. So, with innovations like these, one of the factors of air pollution can be mitigated.”